A car accident rate due to driver's mobile phone use while driving a vehicle has been increased. Therefore, the usage of a mobile phone while driving is restricted by law and it is recommended to use a hands-free device.
However, the hands-free device supports only a voice call function such that text messaging cannot be performed via the hands-free device.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.